PRP (Platelet-Rich Plasma)
Blood is a tissue which contains many materials, one of which is platelets. Platelets are packed with numerous factors (growth factor molecules and cytokines) that can attract cells to come into an injured area and for existing cells to “wake up” and accelerate healing. When healing has stalled, PRP has been shown to initiate tissue repair. It can activate tendon cells to heal, bone to regenerate, and can stimulate new blood vessel development and the wound healing process. It has even been shown to normalize the lining of joints and return them to a more youthful and less inflammatory state.
Where Does PRP Come From?
PRP is simply a concentrate of your own blood, after centrifugation and careful isolation under sterile conditions. From your standpoint, it is just like a mini-blood donation and a short wait for processing and ultrasound-guided injection. It is done in one clinic appointment time from start to finish.
What are Growth Factors and Cytokines?
A growth factor is a naturally occurring substance capable of stimulating cellular growth, proliferation, healing, and cellular differentiation. Seven key growth factors that are known to be key to the healing process are bound to platelets in high concentrations, which is why we can activate and attract cells in or near the injury to kickstart the process of regeneration and healing. Cytokines are a category of small proteins that are important in cell signaling. Their release has an effect on the behavior of cells around them, and so they have an important role in helping the healing process organize around the injury.
Scientific Information about PRP and Stem Cells
Healing is a complex process of tissue and cellular interactions with the goal of restoring structure and physical properties to damaged tissues. The musculoskeletal system is composed of different types of connective tissues. Each type of connective tissue (muscle, tendon, ligament, intervertebral disc, joint cartilage, and bone) has a unique structure, function, and remodeling process. When damaged, they demonstrate unique healing processes. However, similarities in the process exist. Understanding these properties of healing is critical in the development and application of regenerative medicine. It is important to realize that both PRP and Stem Cell therapy contain growth factors and cytokines (see above). The differences are that Stem Cell offers many, many more of these, and crucially, that only Stem Cell Therapy has active, living cells that can differentiate into connective tissues themselves, “talk” to other nearby cells through cell-to-cell (paracrine) signaling and really crank up the process.
What Do PRP and Stem Cell Therapy Do to Improve Healing?
As stated above, PRP has been shown to initiate tissue repair. How are some ways that it does this?
Recruitment of mesenchymal stromal cells and stem cells to the injury. Both PRP and stem cell therapies can draw in the right types of cells from local bone marrow, muscle and other tissues into the injured area. Once there, these cells act like a massive engineering and construction crew to restore the injured structure. Here is an abstract of an open-source article just out from Cornell University that explains this in more detail.